Toggle clamp

ABSTRACT

A toggle clamp includes a base that pivotally supports a pair of jaws which have respective overlapping portions that support respective clamping portions. Movement of the jaws between an unclamped position and any one of a plurality of clamped positions, in which the clamping portions cooperate in a variably spaced clamping relationship, is controlled by a pair of toggle linkages respective to the jaws. Each linkage includes first and second links which are coaxially pivoted to each other at respective ends thereof and to common connecting links that extend between the linkages to coordinate the movements thereof. The other ends of the first links are pivoted to the respective jaws and the other ends of the second links are pivoted to respective ends of respective support links. The other ends of the support links are coaxially pivoted to the base and a pair of helical springs extends between the base and the support links to selectively and alternately bias the linkages overcenter to either folded released positions or generally unfolded unreleased positions. With the linkages in the released positions, the jaws are positioned in the unclamped position. Actuation of an air cylinder bodily shifts the linkages overcenter from the released positions to the unreleased positions in which the jaws are positioned in the clamped position providing the required spaced clamping relationship.

United States Patent Schraner 1 3,689,058 1 Sept. 5 1972 [54] TOGGLE CLAMP [72] Josef F. Schraner, Mount Clemens,

Mich.

[73] Assignee: General Motors Corporation, Detroit, Mich.

Filed: Nov. 19, 1970 Appl. No.: 90,949

Inventor:

[56] References Cited UNITED STATES PATENTS 2,260,61 l 10/1941 DiSanto ..269/32 X 3,028,577 4/1962 Strauss "269/228 X 2,817,254 12/1957 Barnes et al. ..294/88 X 3,480,271 11/1969 Coutilish ..269/228 Primary Examiner-Theron Condon Assistant ExaminerNeil Abrams Attorneyw. E. Finken and Herbert Furman A toggle clamp includes a base that pivotally supports a pair of jaws which have respective overlapping portions that support respective clamping portions. Movement of the jaws between an unclamped position and any one of a plurality of clamped positions, in which the clamping portions cooperate in a variably spaced clamping relationship, is controlled by a pair of toggle linkages respective to the jaws. Each linkage includes first and second links which are coaxially pivoted to each other at respective ends thereof and to common connectinglinks that extend between the linkages to coordinate the movements thereof. The other ends of the first links are pivoted to the respective jaws and g the other ends of the second links are pivoted to respective ends of respective support links. The other ends of the support links are coaxially pivoted to the 7 base and a pair of helical springs extends between the 3 Claims, 8 Drawing Figures Patented Sept. 5, 1972 3 Sheets-Sheet 1 .Q v Q R x Q N m mm v ATTORNE( Patented Sept. 5; 1972 3 Sheets-Sheet 2 Jrsef 5? ATTORNEY TOGGLE CLAMP This invention relates to toggle clamps and more particularly to a toggle clamp in which a jaw is adjustably positioned in clamped position by a toggle linkage.

Toggle clamps conventionally include a base that supports a jaw for movement between an unclamped position and a clamped position in which a clamping portion on the jaw cooperates in a spaced clamping relationship with another clamping portion mounted on the base. One manner in which these clamps are utilized is to index vehicle bodies between successive welding stations during assembly of the bodies. This is accomplished by engagement of the clamping portions with pusher plates, mounted on body trucks that support the vehicle bodies during assembly, and subsequent movement of the clamps and consequently the trucks and bodies to the various stations. Due to the fact that these trucks are recycled through the assembly line and generally reworked for reuse in successive model years, the pusher plates have quite a tendency to wear, however, not necessarily at uniform rates. It is, therefore, necessary that the clamping portions securely engage the pusher plates despite the variance in thickness among the plates.

This invention proves a toggle clamp in which the jaw is adjustably positioned in any one of a plurality of clamped positions by a toggle linkage such that the clamping portions can clamp pusher plates that have a variance in thickness.

Accordingly, an object of this invention is to provide a toggle clamp in which the jaw is adjustable positioned in any one of a plurality of clamped positions by a toggle linkage to allow a variance in the spacing between the clamping portions of the clamp.

In carrying out this object, the clamp of this invention includes a toggle linkage that has a plurality of links connected in series. One end of the linkage is connected to the jaw and the other end of the linkage is adjustably supported on the base such that the linkage bodily shifts from a folded released position to an unfolded unreleased position to move the jaw from an unclamped position to a selected clamped position in which the clamping portions cooperate in the required spaced clamping relationship. Actuating means connected to the linkage bodily shifts the linkage between the released position and the unreleased position to thus control movement of the jaw between the unclamped position and the clamped positions.

In the preferred embodiment, the clamp includes two overlapping jaws that support respective clamping portions and have respective linkages. Each linkage includes two links connected in series and common connecting links extending between the linkages coordinate the movement thereof. Support links pivoted to the respective linkages and to the base are spring biased to selectively and alternately bias the linkages overcenter to either the folded released positions or the generally unfolded unreleased positions.

In the Drawings:

FIG. 1 is an elevation view of the clamp with the jaws in a clamped position;

FIG. 2 is a view similar to FIG. 1 but with the jaws in the unclamped position;

FIG. 3 is a plan view taken generally along line 3-3 of FIG. 1;

FIGS. 4 and 5 are enlarged sectional views generally taken along lines 4-4 and 5-5 of FIG. 3, respectively;

FIG. 6 is a sectional view of a portion of the clamp taken generally along line 6-6 of FIG. 3 with the jaws in a clamped position;

FIG. 7 is a view similar to FIG. 6 but with the jaws in the unclamped position; and

FIG. 8 is an enlarged sectional view of a portion of the clamp taken generally along line 8-8 of FIG. 6.

Referring now to the drawings, and more particularly to FIGS. 1 through 3, a toggle clamp according to the invention is generally indicated at 10 and includes a support plate 12 that supports a base 14 by way of spacers 16. Spaced side walls 18 are welded or otherwise suitably mounted on base 14 and are slightly relieved on their outer sides at 20 intermediate apertures 22 adjacent the ends of walls 18. Adjacent the left-hand end of the clamp 10, a plate 24 extends between walls 18 and mounts spaced upstanding ears 26. A pin 28 extends between ears 26 to pivotally support the left-hand apertured end of a first jaw 30 which is received therebetween. Adjacent the right-hand end of the clamp 10, a plate 32 extends between the walls 18 and supports an upstanding ear 34 by way of lower flanges 36 thereof. A second jaw generally indicated at 38 includes laterally symmetrical jaw portions 39 and 40 that are spaced with respect to each other by spacers 41, as seen in FIG. 3. Ear 34 is received between the jaw portions 39 and 40 to pivotally support the righthand apertured end of jaw 38 by way of a pin 42. Intermediate the ends of clamp 10, jaw 30 is received between jaw portions 39 and 40 of jaw 38 such that the jaws overlap each other and respectively support clamping portions 44 and 46 in opposed relationship. A pair of guide plates 48 are secured to side walls 18 by screws 50 and respectively engage jaw portions 39 and 40 to prevent lateral deflection of the jaws during movement between unclamped position, FIGS. 2 and 7, and clamped position, FIGS. 1 and 6, in which a pusher plate member 52 of a body truck is clamped between clamping portions 44 and 46 as will be described.

Referring now to FIGS. 6 and 8, a first toggle linkage generally indicated at 54 includes spaced links 56 whose upper ends are pivoted to jaw 30 by a pin 58 and a bushing 60. Bushing 60 is of the same type as other bushings used in clamp 10 and includes a sintered thin porous layer of spherical bronze impregnated with a Teflon and lead compound such that bushing is selflubricating thus minimizing the maintenance required to assure smooth operation of clamp 10. The lower ends of links 56 are pivoted to a bushed pin 62 and are spaced by an actuating member 64 which controls movement of clamp 10 as will be described. Linkage 54 also includes spaced links 66 whose upper ends are also pivoted to the bushed pin 62 and whose lower ends are secured to a pin 68. A first support link has a bushed end pivoted to pin 68 between links 66. As seen in FIG. 5, the other end of link 70 includes spaced cars 72 which are pivoted to a side wall mounted bushed pin 74. Base 14 includes an aperture 75 that receives the lower end of helical spring 76 whose upper end is received within an aperture 77 in support link 70. Spring 76 biases link 70 upwardly and controls movement of linkage 54, as will .be-described.

Referring now to FIGS. 4 and 6,, a second toggle linkage generally indicated at 78 includes a link 80 whose upper end supports a pin 82 that is pivoted to bushed jaw portions 39 and 40. The lower end of link 80 is pivoted to a bushed pin 84 with spacers 86 on each side thereof. Linkage 78 also includes a pair of spaced links 88 that have their upper ends pivoted to bushed pin 84 and their lower ends secured to a pin 90. A second support link 92 has a bushed end pivoted to pin 90 between the lower ends of links 88. The other end of link 92 is pivoted to the bushed pin 74 between spaced ears 72 of link 70. Base 14 includes an aperture 93 that receives the lower end of a helical spring 94 whose upper end is received within an aperture 95 within link 92. Spring 94 biases link 92 upwardly to control movement of linkage 78, as will be described.

As best seen in FIGS. 3 and 6, the side walls 18 are cut away at 96 such that pins 62 and 84 extend laterally outwardly thereof. Connecting links 98 extend between pins 62 and 84 on the respective outer sides of walls 18 to coordinate movement of linkages 54 and 78, as will be described.

As seen in FIGS. 1 and 2, an air cylinder 100 is pivoted to base 14 by a pin 102 and includes a piston having a rod 104 that is connected to actuating member 64 to control movement of the toggle linkages 54 and 78. Suitable means, not shown, supplies air pressure to opposite sides of the piston within cylinder 100. The air pressure supply is controlled by switches 106 and 108 secured to the outer side of the one side wall 18 by screws 109. Switches 106 and 108 are respectively controlled by vanes 110 and 111 secured to the jaws by bolts 112. During movement of the jaws between a selected clamped position and the unclamped position, vanes 110 and 111 are respectively guided by slotted brackets 113 and 114 secured to the one side wall 18 by bolts 1 15. Movement of the jaws to the unclamped position terminates the air pressure supply to air cylinder 100 and the upward bias of springs 76 and 94 on links 70 and 92 holds the linkages 54 and 78 in the folded released positions of FIGS. 2 and 7 in cooperation with a leg 116 of link 72 that engages a base wall mounted pin 118. This engagement also prevents upward floating movement of linkage 54 and a consequent movement of jaw 30 toward clamped position. Similarly, a pin 119, that is mounted on the right-hand end of jaw 30, engages jaw portions 39 and 40, as in FIGS. 2 and 7, to prevent movement of jaw 38 toward a clamped position due to upward floating movement of linkage 78. Also, a stop 120, mounted on a plate 121 extending between side walls 18, can be adjusted to engage the jaw 38 concomitant with or slightly after the engagement of leg 116 with pin 118 to cooperate with pins 1 l8 and 1 19 in positioning the jaws 30 and 38 in the unclamped position or to provide a backup stop.

When it is desired to clamp pusher plate member 52 between the clamping portions 44 and 46, member 52 is moved to a position above clamp 10, as in FIGS. 2 and 7, and clamping movement of jaws 30 and 38 is accomplished as follows. Air pressure is supplied to the piston within cylinder 100 to move rod 104 outwardly and actuating member 64 to the right. This causes the toggle linkages 54 and 78 to unfold from their released positions, thus moving to straightened positions and subsequently bodily shifting overcenter to the unreleased positions of FIGS. 1 and 6 in which the righthand ends of connecting links 98 engage side wall mounted stops 122. This movement of linkages 54 and 78 causes the jaws 30 and 38 to pivot upwardly to a clamped position in which clamping portions 44 and 46 engage opposite sides of member 52. Links and 92 and springs 76 and 94 adjustably position the linkages 54 and 78 in the unreleased positions and, as such, the jaws are adjustably positioned in clamped position. Consequently, it is possible for the thickness of member 52 to vary between maximum and minimum limits and jaws 30 and 38 will assume the required clamped position in which the clamping portions 44 and 46 are positioned in the required spaced clamping relationship.

If the air cylinder is actuated without a member between the clamping portions 44 and 46, linkages 54 and 78 will 'unfold and move overcenter with connecting links 98 engaging stops 122. The springs 76 and 94 will then cause support links 70 and 92 to move linkages 54 and 78 upwardly while the ends of connecting links 98 slide upwardly along stops 122. Before clamping portions 44 and 46 engage each other and before the ends of connecting links 98 reach the top of stops 122, leg 116 of support link 70 engages pin 118, thus preventing further movement of jaws 30 and 38 upwardly and possible damage to clamp 10.

The invention thus provides a toggle clamp in which a jaw is adjustably positioned in any one of a plurality of clamped positions to provide the required spaced clamping relationship between the clamping portions of the clamp.

What is claimed is:

1. A toggle clamp comprising, a base, first and second jaws including respective clamping portions, means mounting the jaws on the base for movement between an unclamped position and any one of a plurality of clamped positions in which the clamping portions cooperate in a variably spaced clamping relationship, a toggle linkage respective each jaw, each linkage including a plurality of links connected in series, one end of each linkage being connected to the respective jaw, means connecting the linkages intermediate the ends thereof for concurrent movement with respect to each other, support means connecting the linkages at the other ends thereof to the base and supporting the linkages for bodily shifting movement overcenter from folded released positions to unfolded unreleased positions to move the jaws from the unclamped position to a selected clamped position positioning the clamping portions in the required spaced clamping relationship, means selectively and alternately biasing the linkages to either the released positions or the unreleased positions, and actuating means for bodily shifting the linkages overcenter between the released positions and the unreleased positions and thereby moving the jaws between unclamped position and a selected clamped position.

2. A toggle clamp comprising, a base, first and second jaws including respective clamping portions, means pivoting the jaws to the base for movement between an unclamped position and any one of a plurality of clamped positions in which the clamping portions cooperate in a variably spaced clamping relationship, a toggle linkage respective each jaw, each linkage including first and second links pivotally connected to each other at respective ends thereof, a common connecting link pivoted to each linkage at the pivotal connection between the first and second links, the other ends of the first links being pivoted to the respective jaws, support means connecting the other ends of the second links to the base and supporting the linkages in cooperation with the connecting link for concurrent bodily shifting movement overcenter from folded released positions to unfolded unreleased positions to move the jaws from the unclamped position to a selected clamped position positioning the clamping portions in the required spaced clamping relationship, means selectively and alternately biasing the linkages to either the released positions or the unreleased positions, and actuating means for bodily shifting the linkages overcenter between the released positions and the unreleased positions and thereby moving the jaws between unclamped position and a selected clamped position.

3. A toggle clamp comprising, a base, first and second jaws including respective overlapping portions respectively supporting first and second clamping portions, means pivoting the jaws to the base for movement between an unclamped position and any one of a plurality of clamped positions in which the clamping portions cooperate in a variably spaced clamping relationship, a toggle linkage respective each jaw, each linkage including first and second links pivotally connected to each other at respective ends thereof, a common connecting link pivoted to each linkage at the pivotal connection between the first and second links, the other end of each first link being pivoted to the respective jaw, a support link respective each linkage, each support link having one end thereof pivoted to the other end of the respective second link, the other end of each support link being pivoted to the base, spring means between the base and the support links selectively and alternately biasing the linkages overcenter to either folded released positions in which the jaws assume the unclamped position or unfolded unreleased positions in which the jaws assume a selected clamped position positioning the clamping portions in the required spaced clamping relationship, and actuating means for bodily shifting the linkages overcenter between the released positions and the unreleased posi-.

tions and thereby moving the jaws between unclamped position and a selected clamped position. 

1. A toggle clamp comprising, a base, first and second jaws including respective clamping portions, means mounting the jaws on the base for movement between an unclamped position and any one of a plurality of clamped positions in which the clamping portions cooperate in a variably spaced clamping relationship, a toggle linkage respective each jaw, each linkage including a plurality of links connected in series, one end of each linkage being connected to the respective jaw, means connecting the linkages intermediate the ends thereof for concurrent movement with respect to each other, support means connecting the linkages at the other ends thereof to the base and supporting the linkages for bodily shifting movement overcenter from folded released positions to unfolded unreleased positions to move the jaws from the unclamped position to a selected clamped position positioning the clamping portions in the required spaced clamping relationship, means selectively and alternately biasing the linkages to either the released positions or the unreleased positions, and actuating means for bodily shifting the linkages overcenter between the released positions and the unreleased positions and thereby moving the jaws between unclamped position and a selected clamped position.
 2. A toggle clamp comprising, a base, first and second jaws including respective clamping portions, means pivoting the jaws to the base for movement between an unclamped position and any one of a plurality of clamped positions in which the clamping portions cooperate in a variably spaced clamping relationship, a toggle linkage respective each jaw, each linkage including first and second links pivotally connected to each other at respective ends thereof, a common connecting link pivoted to each linkage at the pivotal connection between the first and second links, the other ends of the first links being pivoted to the respective jaws, support means connecting the other ends of the second links to the base and supporting the linkages in cooperation with the connecting link for concurrent bodily shifting movement overcenter from folded released positions to unfolded unreleased positions to move the jaws from the unclamped position to a selected clamped position positioning the clamping portions in the required spaced clamping Relationship, means selectively and alternately biasing the linkages to either the released positions or the unreleased positions, and actuating means for bodily shifting the linkages overcenter between the released positions and the unreleased positions and thereby moving the jaws between unclamped position and a selected clamped position.
 3. A toggle clamp comprising, a base, first and second jaws including respective overlapping portions respectively supporting first and second clamping portions, means pivoting the jaws to the base for movement between an unclamped position and any one of a plurality of clamped positions in which the clamping portions cooperate in a variably spaced clamping relationship, a toggle linkage respective each jaw, each linkage including first and second links pivotally connected to each other at respective ends thereof, a common connecting link pivoted to each linkage at the pivotal connection between the first and second links, the other end of each first link being pivoted to the respective jaw, a support link respective each linkage, each support link having one end thereof pivoted to the other end of the respective second link, the other end of each support link being pivoted to the base, spring means between the base and the support links selectively and alternately biasing the linkages overcenter to either folded released positions in which the jaws assume the unclamped position or unfolded unreleased positions in which the jaws assume a selected clamped position positioning the clamping portions in the required spaced clamping relationship, and actuating means for bodily shifting the linkages overcenter between the released positions and the unreleased positions and thereby moving the jaws between unclamped position and a selected clamped position. 